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First of all I would like to explain that this is the last question I need to answer to complete an assignment that consisted of 20 University of Waterloo SIN Contest questions. This question is from the 1999 SIN contest. I would ask my Physics teacher for help but it is now the weekend and the assignment is due on Monday so I have come here looking for aid.
PS. The question itself is kind of a Canadian politics joke.
Big Jean Chretien. in a liberal mood. throws a carton of pepper spray at Lucien Bouchard. (Assault by pepper?). Lucien catches the carton, and hangs onto it, of course. (Has he ever returned a federal gift?). Since both men were initially standing at rest on a frictionless horizontal ice surface, this exchange causes them to separate. Each man has a mass of 100 kg, the carton has a mass of 20 kg, and the carton left Jean's hands with a horizontal velocity of 10 m/s relative to Jean's body. Calculate the final relative separation speed between the two men. (Answer in m/s).
(a) 2.7
(b) 3.1
(d) 7.1
(e) 8.9
(c) 5.2
Pt = Pt'
Pt' = P1' + P2' (Similar to Pt)
P1 = m1v1 (Similar to P2, P1', P2' etc...)
m1v1 + m2v2 = m1v1' + m2v2'
P = Momentum
m = Mass
v = Velocity
Ok so, the first thing i did is find the speed of Lucien Bouchard. Since the 20kg projectile sticks to him once he catches it then we know that v1' = v2' = v'
Knowing that:
Pt = Pt'
m1v1 + m2v2 = m1v1' + m2v2'
m1v1 + m2v2 = m1v' + m2v'
m1v1 + m2v2 = v'(m1 + m2)
(20)(10) + (100)(0) = v'(20 + 100)
v' = 1.67 m/s
Now to find the speed of Jean Chretien. To find this one I used a similar equation but since he is not moving before he throws the projectile Pt = 0.
Pt = Pt'
0 = Pt'
0 = m1v1' + m2v2'
m1v1' = m2v2'
(100)v1' = (20)(10)
v1' = 2 m/s
This would give me a final relative separation speed of:
v = v'  (v1')
v = (1.67)  (2)
v = 3.67 m/s
And since this is not one of the multiple choice answers it means that I did something wrong somewhere.
Any help would be greatly appreciated, especially before monday . And if there is anything you guys don't understand then please ask and I will explain more thoroughly.
Attached is a .pdf file with a scan of the question and my rough work.
Thanks in advance.
 Stahs
PS. The question itself is kind of a Canadian politics joke.
Homework Statement
Big Jean Chretien. in a liberal mood. throws a carton of pepper spray at Lucien Bouchard. (Assault by pepper?). Lucien catches the carton, and hangs onto it, of course. (Has he ever returned a federal gift?). Since both men were initially standing at rest on a frictionless horizontal ice surface, this exchange causes them to separate. Each man has a mass of 100 kg, the carton has a mass of 20 kg, and the carton left Jean's hands with a horizontal velocity of 10 m/s relative to Jean's body. Calculate the final relative separation speed between the two men. (Answer in m/s).
(a) 2.7
(b) 3.1
(d) 7.1
(e) 8.9
(c) 5.2
Homework Equations
Pt = Pt'
Pt' = P1' + P2' (Similar to Pt)
P1 = m1v1 (Similar to P2, P1', P2' etc...)
m1v1 + m2v2 = m1v1' + m2v2'
P = Momentum
m = Mass
v = Velocity
The Attempt at a Solution
Ok so, the first thing i did is find the speed of Lucien Bouchard. Since the 20kg projectile sticks to him once he catches it then we know that v1' = v2' = v'
Knowing that:
Pt = Pt'
m1v1 + m2v2 = m1v1' + m2v2'
m1v1 + m2v2 = m1v' + m2v'
m1v1 + m2v2 = v'(m1 + m2)
(20)(10) + (100)(0) = v'(20 + 100)
v' = 1.67 m/s
Now to find the speed of Jean Chretien. To find this one I used a similar equation but since he is not moving before he throws the projectile Pt = 0.
Pt = Pt'
0 = Pt'
0 = m1v1' + m2v2'
m1v1' = m2v2'
(100)v1' = (20)(10)
v1' = 2 m/s
This would give me a final relative separation speed of:
v = v'  (v1')
v = (1.67)  (2)
v = 3.67 m/s
And since this is not one of the multiple choice answers it means that I did something wrong somewhere.
Any help would be greatly appreciated, especially before monday . And if there is anything you guys don't understand then please ask and I will explain more thoroughly.
Attached is a .pdf file with a scan of the question and my rough work.
Thanks in advance.
 Stahs
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